Six antigenic determinants in the surface layer of the archaebacterium Methanococcus vannielii revealed by monoclonal antibodies.

The immunogenicity and antigenic characteristics of the unique surface layer (S layer) of Methanococcus vanielii was studied with a panel of six monoclonal antibodies. Six surface determinants were identified for the first time, each recognized by one antibody exclusively. The determinants are proteins, located in the S layer, and accessible to antibody in whole, unfixed, as well as formalinized bacteria. Hence the six antigens and antibodies reported here should be useful for rapid identification of new isolates and for taxonomy of methanogens, notably Methanococcaceae. In this connection two novel applications of the slide immunoenzymatic assay were developed for analyses of monoclonal antibodies and their complementary sites in the bacterial envelope.